Articulated boom structures, with each boom having the capability of being extensible, and mounted on a prime mover such as a truck or like vehicle have been known for a number of years. The boom structures are usually mounted on a support itself mounted on the prime mover for rotation in a horizontal plane, and are either articulated by hydraulic means, such as a piston and cylinder, or by reel and cable means operated by winches. The boom structures have the primary purpose of placing the innermost end thereof at a location where either a personnel carrier, such as a bucket or work platform can be located for maintenance or construction purposes, or where a working unit, such as a cable and hook may be placed for raising or lowering equipment purposes.
The general hydraulic electric and control equipment and functions of this type of equipment are well known in the field of art. Two examples of articulated and extensible boom structures are shown in U.S. Pat. Nos. 3,262,517 and 3,498,474 issued respectively to Malec and Pierce, Jr.